Actress Maria Conchita Alonso had a furious bust-up with Sean Penn in front of stunned airport staff after she confronted him over his support for controversial Venezuelan President Hugo Chavez.

The former “Colors” co-stars fell out last year when Alonso publicly criticized Penn’s backing of Chavez and penned an open letter urging him to investigate “the dark side behind the person you choose to idolize.”

And she stepped up the feud after spotting the Penn at Los Angeles’ LAX airport on Sunday, branding him a “communist a–” in an angry clash as shocked airline staff and passengers looked on.

Alonso tells New York Post gossip colum Page Six, “I was very calm. I said, ‘I would like to talk to you.’ He said, ‘I have nothing to say to you… You have been saying a lot of things about me in the press.’ I said, ‘How can you defend Chavez?’

“I said, ‘You are a communist, Sean Penn.’ He said, ‘You are a pig!’ So I said, ‘And you are a communist a–! Is it great to live the way you do as a communist?’
“I went back to my mother, and he started yelling at us. I yelled back, ‘Communist a–!’ Nearly 60 people were watching, shocked.”

Penn tells the publication, “I only knew that a hostile woman was nonsensically berating me. I didn’t realize it was that actress. I think I worked with her once. But she looks really different. She was uninformed and impolite to all the other passengers.”

Alonso later apologized for the incident, telling WMAL radio, “I do apologize… He is an intelligent man… But if someone calls me a pig, I am not going to turn the other cheek. But I don’t regret calling him a communist.”